Date is Before Past Date

I am trying to remove values from an adjusted statistical forecast key figure in previous periods; however, I am receiving a message saying that values are ignored because "Date is Before Past Date". In my planning area set up I have all of the key figures set to be able to change history, and the data view that I am working is changeable for the entire time period I am working in. Has anybody run into this before? Is there another settiing somewhere that I am missing that will allow me to change history? We are running SCM 7.0.